A gas turbine, such as an industrial, aircraft or marine gas turbine generally includes, in serial flow order, a compressor, a combustor and a turbine. The turbine has multiple stages with each stage including a row of turbine nozzles and an adjacent row of turbine rotor blades disposed downstream from the turbine nozzles. The turbine nozzles are held stationary within the turbine and the rotor blades rotate with a rotating shaft. The various turbine stages define a hot gas path through the turbine.
During operation, the compressor provides compressed air to the combustor. The compressed air is mixed with fuel and burned in a combustion chamber or reaction zone defined within the combustor to produce a high velocity stream of hot gas. The hot gas flows from the combustor into the hot gas path of the turbine via a turbine inlet. As the hot gas flows through each successive stage, kinetic energy from the high velocity hot gas is transferred to the rows of turbine rotating blades, thus causing the rotating shaft to rotate and produce mechanical work.
It may be desirable to obtain information regarding various components of the gas turbine during operation, such as operating temperatures, which can be measured by thermocouples, or strain, which can be measured by strain gauges. The measurements obtained by these sensors can be wirelessly transmitted from an antenna located on the rotating shaft of the gas turbine to a stationary antenna located in close proximity to the rotating antenna. However, thermal expansion of the rotating shaft can cause the rotating antenna to be moved away from the stationary antenna, leading to reduced signal strength from the rotating antenna and possibly loss of a communication link between the stationary antenna and the rotating antenna.